Power lawn mower



Dec. 31, 1940. A. R. COOPER POWER LAWN MOWER Filed March 27, 1939 Patented Dec. 31, 1940 I v UNITED STATES PATENT orrics POWER LAWN MOWER Allyn R. Cooper, Marshalltown, Iowa, assignor to Cooper Manufacturing Company, Marshalltown, Iowa, a corporation of Iowa Application March 27, 1939, Serial No. 264,381 4 Claims. (Cl. 192-66) An object of my invention is to provide a lawn plurality of pins 35 spaced from the axis of the mower having improved details of construction shaft 2| and arranged substantially parallel which make the manufacturing of the lawn mowthereto. The clutch disc 3| is provided with a er much simpler and inexpensive, yet the lawn plurality of bores 31 to slidably receive the pins 6 mower, when manufactured in accordance with 35. The clutch shaft 33 is joumalled in bearmy disclosure, has a relatively long life as comings 38 and 39 .which are supported in a stapared tothe types of mowers now on the martionary bracket 40 and in the clutch disc 3| reket. spectively. The clutch disc 32 is slidably and A further object is to provide a lawn mower 'non-rotatably mounted on the driven shaft 33 with power means to drive the cutter and the by means of keys 4| and key ways 42. A spring 1 ground wheels thereof and including a clutch 43 is interposed between the clutch disc 32 and mechanism which is simple to construct and efthe bearings 38.

flcient in operation with a minimum of strain and The bearing 39 is provided with a washer 44 wear thrown onto the parts when the clutch is which serves as a stop shoulder for the disc 3|. in either engaged or disengaged position. A friction plate or disc 36 is mounted between 15 The foregoing, other and further objects of the discs 3| and 32 and is formed of suitable the present invention will be in part obvious from friction material. the accompanying drawing and in part pointed The disc 32 is provided with an annular groove out as the description of the invention pro- 45 adapted to slidably receive clutch shoes 45.

gresses. In describing the invention in detail The clutch shoes 46 are provided with pintles 41 20 reference will be made to the accompanying pivoted in a clutch Y The Clutch y drawing wherein is illustrated an embodiment 48 is pivot to D 49 Carried y e b ac et of the invention, like reference characters desiga hes a lever 50 extending therefrom.

nating corresponding parts throughout the sev- A control lever 5| is pivoted on the handle |3 eral views. In said drawing: and connected by a. rod 52 to the clutch lever 25 Figure 1 is a perspective view of a power lawn 5 vIn t e e ea p s o Figure 1 the mower embodying my invention; spring 43 is free to engage the clutch discs 3| Figure 2 is an enlarged sectional view through and 32 with each o her through the medium of the clutch mechanism thereof; the interposed disc 36 as shown in Figure 2. The

Figure 3 is a sectional view on the line 3-3 control lever 5| is pivoted at 53 to the handle 30 of Figure 2 showing an operative connection l3 and When the lever is swung rearwerdly t e between a power shaft and a clutch disc; and clutch disc 32 will be moved away from the clutch Figure 4 is a plan view looking in the direction disc 3| against the action of the sp 3 until of the arrow 4 adjacent Figure 1 and showing the rod 52 passes over center with relation to the a clutch throw-out yoke. pivot 53 and engages a stop pin 54, I On the accompanying drawing I h v u d th In the operation of my clutch structure, when reference numeral In to indicate a, platform, the clutch lever 50 is released it permits the The platform It] is supported by gr und wheel spring 43 to expand and force the clutch discs 3|, l2 and in turn supports a motor M. A handle 32 and 36 into eng Wi h each other.

13 is provided for the lawn mower for conven- This results in the disc 3| enga the stop 40 ience in controlling and steering it. washer 44 and thus all rotating load on the bear- A cutter shaft I4 is provided o hi h i ings 38 and 39 is eliminated. When the clutch mounted a reel including spiders I5 and reel bars i engaged and revolving there is obviously 0 It. The reel bars 16 cooperate with a stationary thrust load on either bearing 38 or 39 as the cutter bar I1 in the usual manner for tti clutch assembly is entirely self-contained and the 45 grass, The cutter shaft 14 is suitably journaled hr f the p i 43 is taken p b tw en the and driven by mechanism including a sprocket bearings with the clutch discs 3|, 32 and 36 in- 23 and a chain 24. terposed between the spring and the bearing 39,

The motor M has a power shaft 2| with which the disc 3| in turn bearing against the washer a clutch indicated generally at C is operatively 44 and thus against the bearing 39. 50 connected. The clutch C drives a sprocket 22 When the clutch is inoperative or disengaged which in turn drives the chain 24. and the motor shaft 2| is rotating thus driving The clutch C includes a pair of clutch discs the clutch disc 3| the right hand portion of the I 3| and 32 and a clutch shaft 33. A spider 34 is clutch is stationary and hence there is no re- 55 mounted on the power shaft 2| and carries a volving load on the bearing 38 and only the 55 weight of the clutch plate 3| on the bearing 39.- This arrangement obviously enables me to provide a clutch which is long wearing and free of, trouble from rotating thrust pressure developed on the bearings.

My clutch cooperates with the mechanism of the mower to produce a quiet running power mower having a relatively long period of useful life before there is any necessity of parts replacement or rebuilding.

In accordance with the provisions of the patent statutes I have described my invention together with the principle of operation thereof. The described form I consider to represent the best embodiment thereof but desire it to be understood that the details of structure disclosed are illustrative only and that the invention may be carried out by other means and mechanical equivalents within the scope of the appended claims.

I claim as new and desire to secure by Letters. Patent of the United States:

1. In a power lawn mower, a power shaft, a spider carried thereby, a plurality of pins projecting from said spider and arranged substantially parallel to the axis of said power shaft, a clutch disc slidably mounted on said pins, a bearing spaced mom and aligned with said power shaft, a driven shaft journalled in said bearing, a second bearing in said clutch disc, said driven shaft being journalled in saidsecond bearing, a second clutch disc slidably and non-rotatably mounted on said driven shaft, a spring interposed between said first bearing and said second disc and normally constraining: said second disc to frictionally engage said first disc, said second bearing having a shoulder acting as a stop for said first disc upon engagement of said second disc therewith. a handle for the lawn mower, a control leconnccted with said control lever and cooperating with said second disc to disengage it from said first disc against the action of said spring,*a cutter-shaft and means for transmitting rotation from said driven shaft to said cutter shaft.

2. In a power lawn mower, a power shaft, a spider carried thereby, a plurality of pins projecting from said spider and arranged substantially-parallel to the axis thereof, a clutch disc mounted on said pins, a bearing spaced from and aligned with said power shaft, a driven shaft second disc to ver mounted thereon for said clutch discs, means journalled in said bearing, a second bearing in said clutch disc, said driven shaft being Journalled in said second bearing, a second clutch disc slidably and non-rotatably mounted on said driven shaft, a spring interposed between said first bearing and said second disc and normally constraining said second disc to frictionally en gage said first disc, a shoulder acting as a stop for said first disc upon engagement of said second disc therewith, a cutter shaft and means for transmitting rotation from said driven shaft to said cutter shaft.

3. In a power lawn mower, a power shaft, 8.

I clutch connected therewith for rotation thereby,

a bearing spaced from and aligned with said power shaft, a driven shaft journalled in said bearing, a second bearing carried by said clutch disc, said driven shaft being journalled in said second bearing, a second clutch disc slidably and non-rotatably mounted on said driven shaft, a

said secondtbearing having spring interposed between said first bearing and said second disc and normally constraining said frictionally engage said first disc, said second bearing having a stop for said first disc upon engagement of said second disc therewith, a control lever cooperating'with said second disc to disengage it from said first disc against the action of said spring, a ground wheel and means to transmit rotation from said driven shaft to said ground wheel.

4. In a device of the class described, a power shaft, a spider carried thereby, a plurality of pins projecting from said spider and arranged substantially parallel to the axis of said power shaft, a clutch disc ,"lidably mounted on said pins, a bearing spaced from and aligned with said power shaft, a driven shaft journalled in said bearing, a second bearing in said clutch disc, said driven shaft being journalled in said second bearing, a second clutch disc slidably and non-rotatably mounted on said driven shaft, a spring interposed between said first bearing and said second disc and normally constraining said second disc to frictionally engage said first disc, said second bearing having a shoulder acting as a stop for said first disc upon engagement of said second disc therewith, and a control lever cosaid second disc to disengage it disc against the action of sa d ALLYN R. COOPER. 

